> For the complete documentation index, see [llms.txt](https://tingreavinash.gitbook.io/the-tech-toolbox/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://tingreavinash.gitbook.io/the-tech-toolbox/notes/build-tools/apache-maven.md).

# Apache Maven

Maven is a popular build automation tool that is widely used in Java projects. It provides a standard way to manage project dependencies, build configurations, and packaging.

### Basic Maven Commands

* `mvn clean`: Deletes the `target/` directory. This command removes all the compiled output and test results.
* `mvn compile`: Compiles the Java source code into bytecode and stores it in the `target/classes/` directory.
* `mvn test`: Runs the tests for the project.
* `mvn package`: Packages the compiled code and resources into a distributable format, such as a JAR or a WAR file.
* `mvn install`: Installs the project artifacts into the local Maven repository.
* `mvn deploy`: Deploys the project artifacts to a remote Maven repository.

### Maven Configuration

* `pom.xml` file: This file is the main configuration file for your Maven project. It defines the project metadata, dependencies, plugins, and build configuration.

#### Project Metadata

* `groupId`: Specifies the group or organization that the project belongs to.
* `artifactId`: Specifies the name of the project.
* `version`: Specifies the version of the project.
* `packaging`: Specifies the packaging format for the project, such as JAR or WAR.

#### Dependencies

* `<dependencies>`: This section is used to declare the dependencies for the project. The most common dependency scopes are:
  * `compile`: Specifies dependencies that are required for compiling the code and for the project to run.
  * `test`: Specifies dependencies that are required for testing the code.
  * `provided`: Specifies dependencies that are provided by the runtime environment, such as the Java API.
  * `runtime`: Specifies dependencies that are required for running the code but not for compiling it.

#### Plugins

* `<plugins>`: This section is used to declare the plugins for the project. Maven provides many built-in plugins, such as `compiler`, `surefire`, and `jar`.
* `<plugin>`: This element is used to define a plugin and its configuration.
* `<execution>`: This element is used to define an execution of a plugin, which can have multiple goals.

### Maven Build Lifecycle

Maven has three built-in build lifecycles: `clean`, `default`, and `site`. Each lifecycle is made up of phases, which represent different stages of the build process.

* `clean`: Deletes the `target/` directory.
  * `pre-clean`: Executes tasks before the clean phase.
  * `clean`: Deletes the `target/` directory.
  * `post-clean`: Executes tasks after the clean phase.
* `default`: Builds and packages the project.
  * `validate`: Validates the project and its dependencies.
  * `compile`: Compiles the Java source code.
  * `test`: Runs the tests for the project.
  * `package`: Packages the compiled code and resources into a distributable format.
  * `verify`: Verifies the integrity of the packaged code.
  * `install`: Installs the project artifacts into the local Maven repository.
  * `deploy`: Deploys the project artifacts to a remote Maven repository.
* `site`: Generates documentation and reports for the project.
  * `pre-site`: Executes tasks before the site phase.
  * `site`: Generates documentation and reports for the project.
  * `post-site`: Executes tasks after the site phase.
  * `site-deploy`: Deploys the generated documentation and reports to a remote server.

### Conclusion

Maven is a powerful build automation tool that provides a standard way to manage project dependencies, build